Business Calculations

There are various business calculations that you need to be able to do.

Here are a couple of common calculations and their steps to help you:

Percentage Increase:

When you go from a small value to a large value over time you need to say:

To do this on your Sharp desktop calculator:

1. Find big – small and press =
2. Then divide your answer by the small value and press =
3. Now multiply by 100 to get your percentage increase.

Percentage Decrease

When you go from a bigger value to a smaller value over time. Your formula is:

To do this on your Sharp desktop calculator:

1. Find big – small and press =
2. Then divide your answer by the big value and press =
3. Now multiply by 100 to get your percentage decrease.

Finding Vat.

Setting the tax / vat rate rate:

Most Sharp desktop calculators follow these steps to set the tax rate.

1. Press C (on twice)
2. Press the +Tax button. On the left hand side you will see underneath the word TAX, RATE in a box. This is showing you what your current tax percentage rate is set to.
3. Type in the rate you want to set your tax to and press =.
4. Now press C again.

If you want to test it, type in 100 and then press the +Tax button, it should then give you 100 + whatever your tax rate was set to. For example, if I set my tax rate to 15, when I test it, it should give me 115.

Finding your total including tax:

Now that your rate is set, it is as easy as pressing whatever your cost before tax is and the +tax button.

If you don’t have a Sharp calculator (don’t dispair all good stationery stores carry them) you can do the calculation manually by saying

1. Your tax rate divided by 100 to get it as a decimal, e.g. 15 divided by 100 = 0.15.
2. Then add it to 1, e.g. 1.15
3. Now multiply the cost you have before tax is added with this rate to get your value with tax included.

Finding the amount of vat payable:

If after the previous calculation, you press the +Tax button a second time, your Sharp calculator will will show you the total tax amount that was added to your original amount.

Again, you can also do this calculation manually by saying:

1. Your tax rate divided by 100 to get it as a decimal, e.g. 15 divided by 100 = 0.15.
2. Then multiply your before tax cost with your decimal to get the tax amount that would be added to your original cost.

Finding the tax amount from the total amount payable:

Ever wondered what you are paying in VAT or tax on everyday items?

You can also do this on your Sharp desktop calculator. Type in the full amount you are paying and press the -Tax button twice. You will get the total tax that is paid.

You can also do this manually:

1. Add your your rate to 100. e.g. 15 + 100 = 115.
2. Take your rate and divide it by your rate plus 100. E.g. 15 divided by 115.
3. Multiply this by the total amount paid to get the tax that was paid.

Finding the original amount before Tax was added.

Again on your Sharp desktop calculator its as easy as typing in the original value and pressing the -Tax button once.

But, if you want to do it the long way…

1. Add your rate to 100. E.g. 15 + 100 = 115
2. Divide this answer by 100. E.g. 115 divided by 100 = 1.15
3. Now divide your original total by the answer in step 2. E.g. 100 divided by 1.15 = 86.96

To test this, take the amount found and add your tax back to it, e.g. 86.96 + 15% (you can do this as stated here on any Sharp calculator). You should get the total amount you started with.

Percentage Calculations

Adding a Percentage to an amount:

You can also add any percentage to your starting amount.

Of course there also two ways here.

The easy way – type in your amount press + and the value of the percentage you want to add, press the percent button and voila. E.g. 120 + 20% = 144

The hard way:

1. Divide your percentage by 100, so that it becomes a decimal. E.g. 20 divided by 100 = 0,2
2. Then add 1 to it.  E.g. 0,2 + 1 = 1,2
3. Now multiply this by your starting amount. E.g. 1,2 x 120 = 144

Subtracting a Percentage:

Again there are two ways to calculate this.

On your Sharp desktop calculator type in your starting amount, press minus and then your percentage value you want to subtract and press the percent button. E.g. 120 – 20% = 96

The long way:

1. Divide your percentage by 100, so that it becomes a decimal. E.g. 20 divided by 100 = 0,2
2. Then subtract this decimal from 1. E.g. 1 – 0,2 = 0,8
3. Now multiply this decimal answer with your starting amount. E.g. 0,8 x 120 = 96.

Not a fan of the long way of doing your business calculations or the maths?

Don’t worry, we have a solution to suit every taste – take a look through our range of desktop or business calculators to find the one that works best for you.

The EL-M335 is new and comes in two colours – pink or Navy blue. Perfect for any desk. It has 10 digits and a rate conversion feature. The calculator is the perfect size for your desk.

Want one right now?

Check out our range on Takealot or Contact us for a quote.